Mass mortality events of aquatic animals have increased over the last decades and may become more frequent in the future due to global changes (Burkholder et al. 1995, McInnes and Quigg 2010, Stauffer et al. 2012). In several cases the causal agent is unknown or its identification takes a long time (La and Cooke 2011).
During the disaster, there are multi-tiered effects and consequently a multidisciplinary and multilevel approach is required to manage the crisis. Communication is critical to maintain a responsible social reputation during the crisis, as it can suffer from shifting reactions to risks (Evensen et al. 2013). However, this is not a self-generating process. The level of community trust in public governance may limit or expand the effects of the disaster (Paolisso and Chambers 2001, Nakayachi 2015). In this study, the factors affecting social responses to a fish kill (Parsons et al. 2006) are investigated by analyzing the welfare effects on the coastal communities of a massive mortality event in the Maliakos Gulf (Aegean Sea) in Greece.
In early spring of 2009 (10/03/2009–18/04/2009), a mass mortality of fish was identified around the coastline of the gulf, with dead fish spread along the coast. Fish within the gulf gradually became disoriented and swam up to the shore to their death. In some cases, fish jumped out of the water to the shoreline, where they remained. On a daily basis during that period, more dead animals were noticed along different points of the coastline, but there was no indication of the causal agent. Furthermore, mortality seemed to be species specific (Table 7.1) because the causal agents seemed to affect grey mullet(Mugil cephalus), common pandora (Pagellus erythrinus), striped bream (Lithognathus mormyrus), white sea bream (Diplodus sargus sargus), brown meagre (Sciaena umbra), skate (Raja spp.), shi drum (Umbrina cirrosa), sand smelt (Atherina boyeri) and round sardinella (Sardinella aurita). Massive mortalities of farmed sea bream (Sparus aurata) were also identified within the cages of a marine grow-out fish farm located in the outer part of the mouth of Maliakos Gulf.
This case contributes to understanding the social reactions to an unknown etiology fish kill crisis that appeared locally for the first time. The managerial/governance problems arising from the extensive uncertainty due to the unpredictable duration of a harmful event that is generated by undetected causes are demonstrated. The communication problems of the long-term delivery of scientific outcomes during the crisis are also discussed. The social responses to the mass mortalities in Maliakos have international application, as experience with the management of fish kill crises is limited (La and Cooke 2011).Thus, it is a challenge to select the most appropriate responses and coping strategies (Bundy et al. 2016), as these events occur worldwide (Steffe et al. 2007) and may become more frequent in the future due to global changes (Adger et al. 2005).
| Dates (2009) | Fish Kill Evidence | Site | Figure 7.2 |
|---|---|---|---|
10/03 |
Dead striped breams (Lithognathus mormyrus), harvest through fishing gears |
AgTrias |
Ia |
11/03 |
Fisheries Authority collect dead fish samples: striped breams (Lithognathus mormyrus) (15–20 kg total weight), gilthead sea bream (Sparus aurata) (n = 1), brown meagre (Sciaena umbra) (n = 1) |
Ag. Marina, Ag. Trias |
IV, Ia |
13/03 |
Experimental sampling through fishing with a dredge for 10 min × 400 m. Harvested striped breams (Lithognathus mormyrus), (n = 9, total weight 2 kg) |
Molos |
Ib |
23/03 |
Dead annular sea breams (Diplodus annularis) and sand smelt (Atherina sp.) |
Livari, Ag. Marina |
IV |
28/03 |
Mass mortalities of farmed gilthead sea breams (Sparus aurata), detected in a cage marine farm located within the outer mouth of the gulf* |
Ag. Serafim |
II |
31/03 |
New dead skates (Raja spp.)(n = 2, total weight 30 kg) reported and several dead striped breams (Lithognathus mormyrus) in different sites |
AgTrias, Karavomylos |
Ia, VII |
02/04 |
Dead round sardinella (Sardinella aurita) |
Karavomylos |
VII |
03/04 |
New dead fish skate (Raja spp.) (n = 1, weight 40 kg) reported and several dead annular sea breams (Diplodus annularis) in different sites |
AgTrias, Skarfia |
Ia, Ib & II |
04/04 |
Grey mullets (Mugil cephalus), gilthead sea bream (Sparus aurata), striped bream (Lithognathus mormyrus) |
Molos, |
Ib |
05/04 |
Common pandora (Pagellus erythrinus), grey mullets (Mugil cephalus), striped bream (Lithognathus mormyrus) |
Kammena Vourla, Raches |
III, VIII |
08/04 |
Grey mullets (Mugil cephalus), sand smelt (Atherina boyeri) and striped bream (Lithognathus mormyrus) |
Ag. Serafim, Raxes |
II, VIII |
09/04 |
Grey mullets (Mugil cephalus), and dead a brown meagre (Sciaena umbra) |
Ag. Serafim, Ag. Marina |
II, IV |
11/04 |
Annular seabream (Diplodus annularis), striped bream (Lithognathus mormyrus) |
Kalogiros |
VI |
13/04 |
Shi drum (Umbrina cirrosa) (n = 2, 5 kg in total) |
Karavomylos |
VII |
14/04 |
Striped bream (Lithognathus mormyrus) |
Kalogiros |
VI |
18/04 |
Sand smelt (Atherina boyeri), striped bream (Lithognathus mormyrus) |
Achladi |
IX |
Source: Department of Fisheries Prefecture of Fthiotis
Actions: I. Samples (dead fish) send to HCMR, & to NIBTPAN (11/03). II. Water samples from Spercheios river delta and sentto HCMR for analysis (23/03). III. HCMR scientists take water and silt (sinks) samples from the Spercheios Delta (26/03). IV. HCMR scientists inspect again the area and take samples for further analysis (07/04).
*Unofficial estimation raised the farmed dead fish to more than 3million (Sentra, 2009).
The I-ADApT approach (Bundy et al. 2016) was used to conceptualize the local socio-ecological experience from the consequences of the massive fish mortalities in Maliakos. This study describes the ecological, social and governing systems that were affected by the fish kill with emphasis on the social reactions to management responses of the public administration. Supporting sources were collected from official administrative documentation, scientific reports, public media references and web sources relevant to the event.
Maliakos Bay is a wide estuary created over the years into a quaternary alluvial plain (Karageorgis et al. 2005) from the Spercheios River in central-western Greece (Aegean Sea) (Figure 7.1). The bay is divided into two parts, the inner having a surface area of 91.5 km2 and the outer extending to the east of the northern headland of Karavomylos and the southern Khilliomilli Cape. The anti-clockwise circulation is supported by the prevailing west-northwest wind that directs water to the south-southeast, contributing to constant mixing of the waters, which is reflected in the homogeneous salinity of the gulf (Christou et al. 1995). The average maximum depth in the main part of the inner bay ranges from 22 to 27 m, whereas in the entrance of the outer part the depth does not exceed 40 m.
The Spercheios River runs for 82.5 km through a valley with intense cultivation (mainly rice), a few olive groves, dry cropland and extensive grassland used for pasture. The river drains an area of 1,664 km2 and discharges large volumes of fresh water at a rate of 68 m3/s (ranking tenth in Greece) carrying a lot of fine-grained silt that is deposited on a delta with an annual capacity of 805 t/km2 (ranking seventh in Greece) (Poulos et al. 1996, Kormas et al. 2003). Meteorological data from 1990 to 2000 show a mean annual precipitation of 535 mm.
The gulf is species rich with a wide range of euryaline marine finfish such as grey mullet; wild Mediterranean sea bass; and a range of sparoids such as gilthead sea bream, annular sea bream, common pandora, striped bream, white sea bream and sharpsnout sea bream. Exploitable finfish of low commercial value, such as sand smelt and round sardinella, are also available for fishing. Furthermore, there are natural populations of several bivalve shellfish species.
Coastal communities occur along the northern part of the Maliakos Gulf (municipality of Stylida), with 12,750 residents, and the southern coastline (municipality of Molos-Ag. Konstantinos), with 12,090 residents. Agriculture, mainly olive trees and related products, are prevalent on both sides of the gulf, with supplementary food processing (olive oil factories, refineries) as minor industries. Limited animal production (sheep and goats) provides supplementary income to the inhabitants.
Fishing activities within the gulf are supported by 12 small-medium fishing ports. Over the last two decades, there has also been limited aquaculture development of mussels (inner gulf) and sea bass/bream (outer gulf).
Tourism on a low to middle scale has developed along the coastline, providing holiday and leisure services to the local population of Fthiotis mainly during the summer season. Additional employment opportunities are offered at the local port of Stylida, which provides ships and boats with technical and supply services.
The eastern part of the Maliakos Gulf, including the Spercheios River Delta, is governed by the municipality of Lamia, the capital of the prefecture. Lamia is the biggest city in the area, with 75,315 residents, and the center of public administration and commercial activities. Employment is available in the commerce and services sectors in addition to traditional crop production (rice, cotton, cereals) along the Spercheios River (and elsewhere) and light industries.
The major stakeholders that were directly affected by the massive fish kill crisis were the fishing communities along the coastline of the gulf. They operated 225 fishing boats in 2009, of a size between 3.5 m and 15.6 m, with an average length of 6.43 m. The engine power for these vessels ranged between 0 and 147.02 KW, with an average of 17.0 KW. Members of these communities represent more than half of the registered 816 full-time fishermen of the prefecture of Fthiotis, a region highly dependent on fishing (Tzanatos et al. 2005), with an annual harvest yield of approximately 2,500 tons representing 2.5 percent to 3 percent of the national fisheries landings. During mass fish mortalities they cancel their fishing efforts, as there is no market for their catches. In addition to the natural fish stock depletion that can take more than two years to recover, the ‘bad name’ of Maliakos as the origin of these fish created negative long-term marketing impacts that exceeded the duration of the event. Fish stock losses also affected a marine grow-out farm of Mediterranean finfish species located in the outer mouth of the gulf. The capacity of this installation was up to 1,270 tons, mainly sea bass and sea bream, per year. Caged fish mortalities (3 million individuals, unofficial estimation) affected the total farmed biomass. One measure to minimize losses was the seasonal transfer of several cages to another farm site owned by the same company outside of Maliakos Gulf.
The dead fish stranded around the coastline had a negative impact on tourist activities in the wider area of the gulf. Fish taverns and restaurants stopped selling fish as consumers did not trust it and avoided seafood. Alternative efforts to promote fish from other origins had similar negative responses. Accommodation operations (hotels, rooms to let, etc.), even several months after the event during the peak summer season, had limited demand as people were afraid to swim in the surrounding areas. Several radio and TV broadcasts addressed the safety of swimming, but they had a negative market impact. This negative trend gradually normalized one to two years after the crisis.
Mussel farmers and shellfish harvesters were in a precarious position at the time of the event because they were worried about their livestock, as well as any indirect consequences to their sales. This concern was mainly due to discussions of the origin of the bivalves rather than the hygiene quality of their products, which are continuously tested before harvesting for human consumption according to legislation (Theodorou et al. 2011). The fish kills did not seriously affect their harvests or their sales. In Maliakos Gulf, there are ten mussel farms with an annual production of approximately 1,500 to 1,700 tons (Theodorou et al. 2015,). Shellfish harvesters, most of them originating from the coastal fishing communities, exploit approximately 700 tons per year of bivalve shellfish, mainly warty venus.
The local governance system during the crisis is shown in Figure 7.3, giving an idea of the information flow during the event. The prefecture of Fthiotis has a Directorate of Primary Production, created by the Fisheries Authority responsible for fisheries and aquaculture, and a Veterinary Authority responsible for animal health, including fish and shellfish and zoo-sanitary control and inspections. The latter is also responsible for harmful algal bloom (HAB) and water quality monitoring and control, as well as bivalve harvesting bans. Also under the umbrella of the prefecture of Fthiotis are the Environmental Authority, responsible for the application of environmental rules, and the Public Hygiene Authority, responsible for the hygiene standards, including water quality inspection and control.
Both authorities refer to the political governor, the prefect of Fthiotis, who was responsible for public relations with regard to the fish kill. Authorities under his guidance provided site inspection and sampling of the dead fish for further analysis. The public governor was also responsible for requesting technical and scientific assistance from the central Ministry of Agriculture and Environment. The port authority and the coastguard/port police are responsible for legislative control of all human activities in and on the sea, including fisheries and aquaculture.
Because the cause of the event was not immediately known, sampling was carried out by the Environmental Authority to check the outlets of land-based facilities (i.e. sewage plants, oil mills) and human activities along the Spercheios River for possible pollution. This authority also can impose penalties where environmental rules have not been implemented.
The time evolution of the fish kill crisis is shown in Table 7.1, and the distribution of the mass mortality over time in Maliakos Gulf is presented in Figure 7.2. The local Fisheries Authority in collaboration with the Veterinary Department measured physicochemical parameters of the seawater and collected samples of fish that had recently died. The oxygen in the water was normal for that season and the fish flesh was in good condition, without disease indications. There was, however, a mucus-like mass covering the surface of their gills. In addition, reports from routine inspection of water surrounding the mussel farms showed that the abundance of HAB species known to affect bivalves, such as the dinoflagellates Karenia brevis, Alexandrium sp., Dinophysis sp. and the diatom Pseudo-nitzschia sp., was low and under the acceptable limit.
The next step was to ask for further scientific assistance from the national Hellenic Center of Marine Research (HCMR) to study the phytoplankton communities and the environmental parameters of the seawater. At that time supplementary support was provided by experts from a) the closest university (Laboratory of Ichthyology & Aquatic Animal Health, Faculty of Veterinary Medicine, University of Thessaly); b) the National Institute of Biochemistry, Toxicology, Pathology & Animal Nutrition (NIBTPAN); c) the National Agricultural Research Foundation (NAGREF); and e) an environmental consulting firm specializing in HAB monitoring (Nearhus OE). Major sampling actions by the local authorities in collaboration with the relevant research bodies are listed in Table 7.1.
The water column was well oxygenated, as was initially reported by the local authorities, but it was stratified with lower salinity and temperature on the surface due to river runoff. Samples tested for organic pollution and heavy metals were within acceptable limits. Similar low concentrations were observed for nitrates, nitrites and ammonium, in contrast to the high concentration of silicates. There was an imbalance of N/P ratios in most samples, indicating a limitation in the availability of nitrogen. Phytoplankton analysis showed dominance of Chatonella sp. in most samples with nitrogen limitation. Chatonella sp. (Raphidophytes) have been identified worldwide as a source of massive fish kills. The ichthyotoxic activity of this microalga appears to irritate fish gills, causing mucus secretion and gill damage. It was concluded that the heavy rainfall before the fish kill event resulted in nutrient loading from large quantities of fresh water from the Spercheios River into Maliakos Gulf. This caused the imbalance of the N/P ratio in the Gulf and provided conditions suitable for a Chatonella sp. bloom (Pagou et al. 2014), which can kill fish. When the bloom collapsed, the gulf returned to its normal conditions, but with a great reduction of the fish stock.
This crisis occurred just once, but the financial and sociocultural problems it caused were evident for two years after the event. The absence of previous experience (cultural models) played a critical role in peoples’ reactions and helped to shift the problem from the natural resources to the society (Evensen et al. 2013).
Fishing activity during the event was cancelled by the fishermen themselves. Despite fish being available (but in less quantities), the market did not accept them, and fishermen asked for compensation for loss of income during that period (10/3/09–18/04/09). Estimation of the losses was based on the average income from harvests over the previous three years during the same period and were estimated to be about 282 euros/day for small fishing boats (<9 m long) and 338 euros/day for big (>9 m long) fishing boats (Nearchos 2009). As there was no rule for this type of disaster or a national budget available to directly compensate the fishermen, there were several demonstrations and complaints at the local level about fishermen’s rights. The fishermen’s problem was amplified by the mass kill being represented as an environmental problem of Maliakos Gulf. This was promoted by environmental NGOs and the local media, which tended to report public opinion and unofficial sources rather than the authorized scientific position on the phenomenon. In this way the risk was amplified, making the problem more complex and adversely affecting the well-being of the coastal communities (Kasperson et al. 2003, Parsons et al. 2006).
A consequence of this harmful communication of contradictions between official (focused on the water analysis and ichthyopathological research results) and unofficial sources (suggesting ‘general pollution’ as the causal agent) was the creation of a negative environmental health image for the Maliakos Gulf at the time and during the following months, which happened to be peak tourism season. This led to a collapse of fish sales as well as local leisure, accommodation and seafood services. Parents were afraid to let their children swim along the coastline and chose other locations for their summer recreation. Consumers refused to eat locally produced fish, even to the end of the year. The prefect of Fthiotis asked attorneys to investigate the confusion created by unofficial sources about the phenomenon. Recovery plans were also developed, which included informing the public through conferences and local meetings, as well as implementing fishing monitoring measures and an ‘early warning’ system to monitor possible HABs in the gulf. Furthermore, the submission for certification of the Maliakos beach with a ‘blue flag’ (European labeling as ideally suited for swimming after specific water quality inspections) was another measure to mitigate the risk perceptions and attitudes concerning hygiene and safe use of the coastal waters for leisure activities.
Losses due to a massive fish mortality crisis may not be limited to the suppression of wild stock, as consumer behavior can be negatively affected. Crisis communication shifted the risk from the dead fish in the sea to human reactions in the market, which contributed to expanding the negative impacts of the disaster. Social responses were critical to the management of the event and were affected by the lack of cultural models, because there had been no similar experience in the past. Community trust of the official opinions of the registered authorities is vital; this must exist in order to be able to directly and positively shape public opinion during a fish kill crisis. Transparency to the public, media and NGOs regarding monitoring activities such as field sampling may increase the credibility of the crisis management process as a whole. Communication is the tool to prevent or remediate the negative effects of an unusual fish mortality event on consumers and the relevant coastal societies. Further research on methods for efficient management of crisis communications between stakeholders during the time between sampling and final outcomes (which can be a long-term process) is recommended.
Adger, W.N., Hughes, T.P., Folke, C., Carpenter, S.R. and Rockström, J. (2005). Social-ecological resilience to coastal disasters. Science 309: 1036–1039.
Bundy, A., Chuenpagdee, R., Cooley, S.R., Defeo, O., Glaeser, B., Guillotreau, P., Isaacs, M., Mitsutaku, M. and Perry, R.I. (2016). A decision support tool for response to global change in marine systems: the IMBeR-ADApT Framework. Fish and Fisheries 17: 1183–1193.
Burkholder, J.M., Glasgow, H.B. and Hobbs, C.W. (1995). Fish kills linked to a toxic ambush – predator dinoflagellate: Distribution and environmental conditions. Marine Ecology Progress Series 124: 43–61.
Christou, E.D., Pagou, K., Christianidis, S. and Papathanasiou, E. (1995). Temporal and spatial variability of plankton communities in a shallow embayment of the Eastern Mediterranean. In: A. Eleftheriou, A.D. Ansell and C.J. Smith (Eds.) Biology and ecology of shallow coastal waters. Olsen and Olsen, Fredensborg, Denmark, pp. 3–10.
Evensen, D.T., Decker, D.J. and Stedman, R.C. (2013). Shifting reactions to risks: A case study. Journal of Risk Research 16: 81–96.
Karageorgis, A.P., Perissoratis, C. and Anagnostou, Ch. (2005). Characteristics of surface sediments. In: E. Papathanassiou and A. Zenetos (Eds.) State of the hellenic marine environment. HCMR Publ., Athens, Greece, pp. 34–42, 360.
Kasperson, J.X., Kasperson, R.E., Pidgeon, N. and Slovic, P. (2003). The social amplification of risk: Assessing fifteen years of research and theory. In: N. Pidgeon, R.E. Kasperson, and P. Slovic (Eds.) The social amplification of risk. Cambridge University Press, Cambridge, pp. 13–46.
Kormas, K.A., Nicolaidou, A. and Thessalou-Legaki, M. (2003). Variability of environmental factors of an eastern Mediterranean Sea river influenced coastal system. Mediterranean Marine Science 4: 67–77.
La, V.T. and Cooke, S.J. (2011). Advancing the science and practice of fish kill investigations. Reviews in Fisheries Science 19: 21−33.
McInnes, A.S. and Quigg, A. (2010). Near-annual fish kills in small embayments: Casual vs. causal factors. Journal of Coastal Research 26: 957−966.
Nakayachi, K. (2015). Examining public trust in risk-managing organizations after a major disaster. Risk Analysis 35(1): 57–67.
NCMR. (1992). Environmental study of the North Evvoikos Gulf. Papathanassiou, E. (Ed.). Technical Report, Athens, Greece, 243 p.
NCMR. (1994). Study of the pollution problems in Maliakos Gulf, related to the aquaculture activities in the area. Anagnostou, Ch., Papathanassiou, E. (Eds) Technical Report, Athens, Greece, 175 p.
Nearchos, O.E. (2009). The massive fish kill phenomenon in Maliakos Gulf (March–April 2010). Prefecture of Fthiotis, 56pp.
Pagou, K., Varkitzi, I., Pavlidou, A., Hatzianestis, I., Psyllidou, R., Kontoyannis, H., Zeri, X., Yiagnisis, M., Rigos, G. and Prapas, A. (2014). First occurrence of the fish killing Raphidophyte Chattonella sp. in Maliakos Gulf, Greece (eastern Mediterranean Sea). In: 14th International Conference on Harmful Algae. Organized by International Society for the Study of Harmful Algae and Intergovernmental Oceanographic Commission of UNESCO 2010. Hersonissos, Crete, 1–5 November 2010, Abstract book (Pagou P and Hallegraeff G, eds), p. 145.
Paolisso, M. and Chambers, E. (2001). Culture, politics, and toxic dinoflagellate blooms: The anthropology of Pfiesteria. Human Organization 60: 1–12.
Parsons, G.R., Morgan, A., Whitehead, J.C. and Haab, T. (2006). The welfare effects of Pfiesteria- related fish kills: A contingent behavior analysis of seafood consumers. Agricultural and Resource Econonomics Review 35: 348–356.
Poulos, S.E., Collins, M.B. and Evans, G. (1996). Water-sediment fluxes of Greek rivers, southeastern Alpine Europe: Annual yields, seasonal variability, delta formation and human impact. Zeitschrift für Geomorphologie 40: 243–261.
Steffe, A.S., Macbeth, W.G. and Murphy, J.J. (2007). Status of the recreational fisheries in two Australian coastal estuaries following large fish-kill events. Fisheries Research 85: 258–269.
Tzanatos, E., Dimitriou, E., Katselis, G., Georgiadis, M. and Koutsikopoulos, C. (2005). Composition, temporal dynamics and regional characteristics of small-scale fisheries in Greece. Fisheries Research 73: 147–158.
Theodorou, J.A., Viaene, J., Sorgeloos, P. and Tzovenis, I. (2011). Production and marketing tends of the cultured Mediterranean mussel Mytilus galloprovincialis L.1819, in Greece. Journal of Shellfish Research 30: 859–874.
Theodorou, J.A., James, R., Tzοvoenis, I. and Hellio, C. (2015). The recruitment of the endangered fan mussel (Pinna nobilis, Linnaeus 1758) on the ropes of a Mediterranean mussel long line farm. Journal of Shellfish Research 34: 409–414.
